Just letting a few people know, I have successfully activated the Debugging Mode. As Binary said, it's definitely not a beginner project. I've been messing with electronics for a good 5-6 years now and I messed up the first Tamagotchi I tried this on. I made sure to heed Binary's advice and get 30 Gauge Wire Wrap and a low wattage soldering iron. I also purchased a pair of helping hands with a magnifying glass out at radio shack (only about $12 or so I believe). With all of this I still managed to botch the first one, I used a little bit too much flux on the contacts and it spilled over to one of the tracks and burned the PCB a bit, so now there's a line going through the middle on the screen. The Tamagotchi still functions, however. The second time around I used a cuetip to apply the flux. Be careful when doing this mod. If you have a rare colour or something like that try it on another one first, you can always swap the circuit boards out (just make sure to be careful with the speaker!).
Anyways, good luck to all who try this, it's definitely a project that'll take you a good 15 minutes to 30 minutes depending on your soldering experience.
[reposted from Tama-Zone]
P.S.
BG93: I'm surprised your method works, though I wouldn't leave it like that for very long. The wire could eventually slip up and end up shorting something on the PCB or just falling off and moving around all together and force you to reset.